If minimum possible work is done by a refrigerator in converting $100 \; g$ of water at $0^{\circ} C$ to ice,how much heat (in calories) is released to the surrounding at temperature $27^{\circ} C$ (Latent heat of ice $= 80 \; cal/g$)? Round to the nearest integer.

For a refrigerator,heat absorbed from the cold reservoir (sink) is $500\, J$ and heat rejected to the hot reservoir (source) is $800\, J$. The coefficient of performance is:

In a refrigerator,one removes heat from a lower temperature and deposits it to the surroundings at a higher temperature. In this process,mechanical work has to be done,which is provided by an electric motor. If the motor is of $1\,kW$ power and heat is transferred from $-3\,^{\circ}C$ to $27\,^{\circ}C$,find the heat taken out of the refrigerator per second,assuming its efficiency is $50\%$ of a perfect engine.

The temperatures inside and outside a refrigerator are $273 \, K$ and $300 \, K$ respectively. Assuming that the refrigerator cycle is reversible,for every joule of work done,the heat delivered to the surrounding will be nearly ........ $J$.

Define and write the formula for the coefficient of performance of a refrigerator.

The efficiency of a Carnot engine acting as a heat engine is $\eta = 1/10$. If it is used as a refrigerator and the work done on the system is $10 \ J$,then the heat absorbed from the low-temperature reservoir is ...... $J$.